THE DIPTEROUS GEXUS DOLICHOPUS IX NOPtTH AMERICA. 271 

 No. 198. DOLICHOPUS PLUMOSUS Aldrich. 



Dolichopus plumosus Aldrich, Kansas Univ. Quart., vol. 2, 1893, p. 18, pi. 1, 

 fig. 16. 



Male. — Length 4.5-5 mm.; of wing 4.5-4.75 mm. Face mod- 

 erately narrow, pale yellow, sometimes almost golden yellow. Front 

 shining green. First two antennal joints yellow, second narrowly 

 black at tip; third joint black, somewhat conical in outline, pointed 

 at tip, about as long as wide. Lateral and inferior orbital cilia 

 3''ellowish, about six of the upper cilia on each side black. 



Thorax green with coppery reflections ; dorsum a little dulled with 

 gray pollen, which is more or less yellowish brown on the disk; 

 pleurae dulled with white pollen. Abdomen green with more or less 

 coppery reflections; the white pollen on its sides extending upon the 

 dorsum but not conspicuous. Hypopygium black with green reflec- 

 tions on basal half; its lamellae large, nearly twice as long as wide, 

 somewhat elliptical in outline, but narrowing into the stem, white 

 or yellowish with a black border, which is broad on apical, narrow 

 on upper margin, jagged and bristly at apex, fringed with black hairs 

 above and a few pale ones below. 



Fore coxae yellow, usually wholly so, their anterior surface covered 

 with white pollen and delicate little yellow hairs with a few black ones 

 along inner and outer edges. Middle and hind coxae blackish with 

 yellow tips. Femora and tibiae yellow. Fore femora with long 

 black hairs on upper edge of basal half, the longest being nearly as 

 long as the width of the femora; they also have long black hair on 

 apical half of posterior side; these are sometimes yellowish. Middle 

 and hind femora each with one preapical bristle, and v/ith delicate 

 little yellow hairs on the lower edge, the hind pair without cilia below. 

 Middle tibiae with a pair of bristles below near apical third and 

 usually with a smaller one near basal third, their basitarsi with a 

 bristle near apical fourth. Posterior tibiae thickened in the middle, 

 their inner surface entirely covered with black hairs. Fore tarsi 

 (fig. 198a) one and a half times as long as their tibiae, sometimes 

 blackened from the tip of the first joint, in others the first three joints 

 are yellow with black tips, last two joints alwaj^s black; first joint 

 three-fourths as long as the tibiae, second half as long as first, third 

 haK as long as second, slightly widened at tip; fourth joint shorter 

 than third, a little compressed, about as wide as long; fifth joint 

 compressed, nearly as long as third and fourth taken together, about 

 two-thirds as wide as long, somewhat oval, but truncate at tip, 

 fringed above with black hairs; empodium white, plume-like, forming 

 a white tip to the tarsi. Middle tarsi a little longer than their tibiae, 

 black from the tip of the first joint. Hind tarsi black, usually the 

 first joint is mostly yellow with only tlie tip black, but sometimes it 



